Unnecessary boxing was removed from tests (#30250)

akka-actor-tests/src/test/java/akka/actor/JavaAPI.java

@@ -194,14 +194,7 @@ public class JavaAPI extends JUnitSuite {
     }
 
     public void onReceive(Object msg) {
-      String reply =
-          String.valueOf(a)
-              + "-"
-              + String.valueOf(b)
-              + "-"
-              + String.valueOf(c)
-              + "-"
-              + String.valueOf(d);
+      String reply = a + "-" + b + "-" + c + "-" + d;
       getSender().tell(reply, getSelf());
     }
   }

akka-actor-tests/src/test/java/akka/actor/StashJavaAPITestActors.java

@@ -16,7 +16,7 @@ public class StashJavaAPITestActors {
       Object msg, int count, ActorRef sender, ActorRef self, UnrestrictedStash stash) {
     if (msg instanceof String) {
       if (count < 0) {
-        sender.tell(Integer.valueOf(((String) msg).length()), self);
+        sender.tell(((String) msg).length(), self);
       } else if (count == 2) {
         stash.unstashAll();
         return -1;

akka-actor-tests/src/test/java/akka/japi/MatchBuilderTest.java

@@ -6,10 +6,7 @@ package akka.japi;
 
 import akka.japi.pf.FI;
 import akka.japi.pf.Match;
-import org.junit.Rule;
 import org.junit.Assert;
-import org.junit.function.ThrowingRunnable;
-import org.junit.rules.ExpectedException;
 import org.junit.Test;
 import org.scalatestplus.junit.JUnitSuite;
 import scala.MatchError;
@@ -47,13 +44,7 @@ public class MatchBuilderTest extends JUnitSuite {
         Double.valueOf(-47110).equals(pf.match(Double.valueOf(4711))));
 
     Assert.assertThrows(
-        "A string should throw a MatchError",
-        MatchError.class,
-        new ThrowingRunnable() {
-          public void run() {
-            pf.match("4711");
-          }
-        });
+        "A string should throw a MatchError", MatchError.class, () -> pf.match("4711"));
   }
 
   static class GenericClass<T> {
@@ -77,9 +68,10 @@ public class MatchBuilderTest extends JUnitSuite {
                   }
                 }));
 
-    assertTrue(
+    assertEquals(
         "String value should be extract from GenericMessage",
-        "A".equals(pf.match(new GenericClass<String>("A"))));
+        "A",
+        pf.match(new GenericClass<>("A")));
   }
 
   @Test
@@ -104,10 +96,6 @@ public class MatchBuilderTest extends JUnitSuite {
     Assert.assertThrows(
         "empty GenericMessage should throw match error",
         MatchError.class,
-        new ThrowingRunnable() {
-          public void run() {
-            pf.match(new GenericClass<String>(""));
-          }
-        });
+        () -> pf.match(new GenericClass<>("")));
   }
 }